Discussion in 'The Bar' started by P-B, Dec 24, 2011.
does having "dual exhaust" on a turbo car make any sense ?
unless it's a "twin turbo" engine
only reason i could think of is the "factory" exhaust was too restrictive but it doesn't necessarily take dual exhaust to get more exhaust flow. a larger pipe, high-flow muffler could do it but usually the car-maker's engineers could take care of it.
"dual exhaust" is "cooler" and looks better on some cars
my buick turbo had single exhaust but when you added a "dump tube" before the cat, you would pick up .5 in the 1/4 mile. that's a lot. people spend thousands trying to get a few tenths. picking up a 1/2 a second just by opening the exhaust is a free and incredible performance enhancement and it wasn't much louder because the turbo acts as a muffler. you would hear a slightly different rumble and a really loud whistle coming from the turbo when you un-capped the exhaust. there was a company that made parts for the GN. there was a pipe that went from the turbo down to the main exhaust system. $25 and they would replace that pipe with this side opening and a cap held on by 3 bolts
GN's ran 13.9 in the 1/4 mile. open the exhaust, take the air cleaner box out and replace with a high-flow k&n filter and slicks would get a stock GN down to 12.5
that's an insane performance gain for very little money
then computer chips came out, on the passenger side kick-panel was a computer, pop out the rom chip and put the new one in and take the car down to near 12.0. having a street car down near 12 flat meant that no one could touch you in a street race. not unless they just rolled some gutted out "not street legal" big-block track car with lots of money and real work done to the motor and usually no power windows or air conditioning
the chip would bump up the timing, richen the fuel mixture, increase boost from a stock 15 psi to anywhere from 19-22 psi (100 octane recommended for the higher turbo boost or the engine would start knocking)
the chip also did something to the throttle position sensor to make the trans shift harder
another cheap trick was changing out the thermostat to a 160 (i think the stock was 180-200) or somewhere in there. turbo cars are all about heat. the colder you could get things, the faster they would run
i can remember rolling out of my garage on a Sunday 4-5am when it was like 10 degrees out, the car was warmed up enough by the time i reached route 33. i would get the car up to about 35, nail the gas pedal to the floor, the car would downshift to 1st gear for about 2 seconds if that and it felt like i was in a rocket
sunday mornings were my fuck around time. i was used to getting up for my 3am job so sunday mornings i'd be awake go out cruising on the empty highways then eventually end up in Atlantic City, make a few grand at the craps table in 5 minutes or less and be on my way home. the valet on sundays at trop world (Tropicana) got to know me. i'd give him a 5 on the way in and usually 25 on my way out if i did good so he always kept my car by the door instead of parking it. he would hold on to my keys so i could bypass the whole window thing
the parkway was empty that early on sundays it was my own personal nascar track for 90 minutes each way
A couple of things. Restriction on the exhaust side will limit the turbine speed. less flow/ less speed
Not sure about the thermostat. The trick with a turbo or any boost system is cold dry air. Cold dry air is less dense therefore you can compress more air than dense wet air. The more air, the more fuel you can burn, the more fuel you can burn the more power you produce. The engine temperature is important for complete combustion. I can't imagine what a chip would do to the trans unless it's tied into the engine ecm system. Most automatic trans shifts are control by a modulator valve that meters the engagement for a smooth shift. This is normally a mechanical function although there is no reason why it couldn't be controlled electronically. You're kind of getting out of my wheelhouse at that point.
Learning to drive stick shift makes people better drivers
Bungee cords > Duct tape.
"For our purposes"
i agree with the cold dry dense air. i always said that on the coldest days of winter, a turbo car will have an advantage over a naturally aspirated engine. the 86/87 GN have the identical engine as the 85 with one exception, with the 86 year they added and "air to air" intercooler to the turbo adding about 40 hp to the specs. in the winter i could just picture all that freezing cold air being forced into the intercooler's "air scoop" that was right under the front bumper. after market performance parts makers made custom intercoolers for the GN where you could pack them with ice or even dry ice usually at the track. i lived about 2 minutes from Raceway Park in Englishtown. just around the time i got my car they added a Friday night "street night", there were developments being built up all around the wooded track so "street night" had to have muffled cars only. anyway, there were a ton of 86/87 buick turbos on street night. they would gather around the water hose area and cool down their intercoolers between races. you wouldn't want to get water near anything else under the hood, especially after you just did a 1/4 mile run. oh and because of the turbo, we could run with our exhaust "open" since the turbo acted as a sort of muffler
oh but getting back to the aftermarket chip, i was wrong about it making the trans shift harder (there was another trick for that) but what the chip did was raise the RPM "shift points" just a tad to squeeze a bit more performance that's pretty much all the chip did was find all the "head room" the Buick engineers left not to push things to the limit and unleashed them all
i had my own trick for maxing out 1st gear. if i put the shifter into 1st, the computer would force the trans into 2nd but at a slightly higher RPM than if you just left it in "drive". it actually gave an edge but it only did that from 1st to 2nd
i can't tell you how many times that came in handy if someone came rolling up next to me looking to race i would make sure to get my car in it's "strike zone" which was between 35-40 mph. i would grab the shifter, force it down into 1st and the car would launch like a rocket and i wouldn't have to worry about hitting 2nd because the computer took care of that for me
there was a simple under the hood trick to getting the trans to shift harder. it's been a long time but i think it had something to do with this cable that was linked to the throttle position sensor. loosen a nut and move the cable forward or backward (took some experimenting)
dropping the thermostat to 160 was something everyone did. i don't know why but it did enhance performance. turbo cars run hot. i've seen the exhaust manifold on passenger side going into the turbo glowing red once on a GN but that's a whole other story. i do know one thing, my car was never faster than when i would first start it up in the morning (let it warm up just a tad) and gave it that first punch of the gas pedal. there were usually long waiting lines to get to the starting line. most people kept their cars turned off while in line, turning them on only for a few seconds to move up in line. another trick for GN owners was the car had an electric fan, you could add a switch to keep the fan running even with the car turned off
one of the biggest things about turbos and racing was the turbo "lag". that's what i believe the exhaust "flow" helped out with the most. if you were at a dead stop and about to race, if you didn't hold the brake down as hard as you could and smash the gas pedal to the floor about 1 to 2 seconds before the green, you got left behind (you could see the turbo boost gauge climbing rapidly as you had both the brake and the gas to the floor)
people weren't big fans of NOS systems due to the wear n tear they put on engine parts but with a turbo car, you could give the engine a little "shot" of NOS when the light turned green and the freezing cold NOS gas would make turbo lag non existent. all it took was to hold the NOS button down for a second and you were taking off from the line like a big block and you didn't have keep the NOS engaged for the entire run
one time after "street night" i still had my slicks on and a bunch of us would gather in this parking lot to chill for a while with our hoods open till the cops kicked us out there was me and two other GN's there and we happened to be sitting right next to a 3 lane highway and decided to go out and catch a red light. i knew my NOS tank had a tiny bit of gas left in it, i had my slicks on (i also had my secret tourque converter on that nobody knew about) all 3 of us rolled out of the parking lot and caught the first red light, when the light turned green, i left both GN's like they were just parked there at the green light. this dude with a mustang 5.0 LX was riding shot-gun inside the GN that was next to me. they were both kinda pricks, especially the driver of the other GN but when the race was over the mustang owner came over to me and was like "that was fucking awesome oatmeal"
i believe the GN was the first car to get a custom NOS "kit" just for that car (i believe they became common after that) there was a pipe that went from the intercooler right into the intake plenum. the NOS kit came with a whole knew pipe with a NOS injection nozzle. you could switch the tiny jets around if you wanted a 75 hp blast which was stock or replace the jets and get a 150 hp shot. then they came out with a throttle switch so you didn't have to fuck around with a button. just flip a switch and when the pedal hit the floor the NOS kicked in
i like blabbing on about this crap i haven't thought about in 20 years
is that jackie ?
miss him. he would have been incredible with Howard at Sirius
i learned to drive stick by watching my school bus driver for 13 years
that and my dad had a 67 Ford F-100 (not sure the 150 was out yet) with "3 on the tree". it took my little brain a few years to figure out what the fuck he was doing because in my head the shifter was only going up and down and i was like "how is 1st gear suddenly 3rd gear???"
SHUT UP I TOLD YOU NOT TO BE STUPID
one time i had a crash course on driving stick. my friend was driving his little Nissan pick-up and got pulled over with no license
cop wouldn't let us leave unless i drove. it was tricky at first. apparently doing it is a lot different than just watching for 13 years
My grandpa (rip) used to put WD-40 on his arthritis knees and knuckles. I used to kid him about getting ready for his lady friends. The old fellow was a chick magnet all the women 18 thru their 70s were always hugging on him and gramps was usually playing grab ass.
Nash Metro from Hell
I saw a similar one in Quebec a few years ago
'68 AC Railbus
Eating milk instead of drinking it...odd even for the UK.
I've been going back and forth with this, I just noticed the little wings.